Collapsible telescoping form.



C. D.\MCARTHUR COLLAPSIBLE TELE SCOPING FORM.

Patented Aug. 25, 191-L WTNESSES ITED STATES AI'E mmm CHARLES 2D.MCAR'IHUR, OF PITTSBURGI-I, PENNSILVANIA. .A.SSIGI TOR T0 THE BLAWCOLLAPSIBLE STE'EL CENTERING- OOMPANY, OF PI'LTSBURGH PENNSYLVANIA ACORPORA'IION OF NEW JERSEY.

COLLA.PSIBLE TELESCOPIIG FORM.

T0 a/LZ whmn 1'xt mag; ooncem:

%e it known that 'I, CHAI%LES D. M0- ARTJIUR, a citizen of the UnitedStates;- residing at Pittsburgh, in the county 0f Al le ghenyeand Stuteof Pennsylvania, have mvented certain new and useful Improvements inCn]lapsible Telescoping Forum, 0f'whi0h the'following is aspecification.

'Ihe invention relates t0 collapsible forms f0r use in forming conduits,sewers und the -like, and particularly to those so arranged forwardthrough the expanded sections; the

provision 0f a circular collapsible form in which improved means areprovided f01' permitting the collapse of 'the sections; the provisiou 0fan improved forrfi of rigid se1f supporting f0rm wherein the interior.ofthe forin when in expanded operative position is free and unob%rructedto permit of bhe passage 0i' ofher: sections therethrough and thepwvision 0f a telescoping construction in which 'tlm vari0us sectionsmay be forwarded from one pnsition of use t0 another Wi)!f1 a minimumexpeuditure of eflor t an with- 0ut the neuessity 0f using carryingeviees, trncks or the 1ike. One embodiment 0f the invention isillusi;rated in the accompanying drawings, whemin:

Fig. 1 ER an endview of one ofthe sem tions employed, the full linesindicatl'ng the expanded 01" operative position 0f the parts and thcdntted lines indicating the collapsed posltiun 01 the arts, and Fig. 2is a longitw din=zl sectim1 thrm1gh the construmign.

In the drmvings only one seciion S 'ShOWH mmphatuiy, but it W311 beundersa'anii tha.t in pmcbica a pluralifiy 0f se ctions placed eex'1d ddetaclmbly seeured togethr are socitionr being detachably S'il- (rmrndtogcihm l. y m2ans 0f beits im;iente in Fi .2. H wiH nisn 1)- understooahnt in opemiing %.hc fmm, the. zwar sections am :'j;u( ccs=sivecoiiapsed und bmugnt forward through the seciions up i Whiih i'hc0ncrete is harmizzg und. scc.n in pr iii0n at -he Specification cfLetters Patent.

Application filed November 3, 1910. Serial N0. 590,567.

u nobstructed Patented Aug. 25', 1914.

is substantially a contim1o-us one.

As indicated in Flg. 2 each section is pro vided with stiflening ribs,l, 2 and 8, a1- though the number' may vary depending upon thecondi'tions, and that sheet me'ml lagging 4 is secured..to the outerside 0f the stiflenin ribs. The stifi'ening ribs am preferably c arme!baz:s althi1gh obviously other 'sections might be employed, und are 0fsufiicient rigidity to: rigidlyund securely support the 1a *ging againstthe prassure 0f the cqncrete wen. the parts are in expanded positionwithout the necessity 0f employizig any transverse braces, the interiorsurface 019 the fotrn nein thus left entirely free and or the passage ofother sections. As indics xted in. Fig.- 1 th'e lagging and 1i'bs am cutalongihe lines 5 und 6 in order 110 provide the fiafi)s 0r wings 7 and8, such wings being hinged'to the main p'0rtion of the forin b means 0ft he hinges 9. The swinging of t ese wings down to the positi0nindicated in dotted lines in"'Fig. 1 perof the form such collapsingbeing efl'ected by means ofthe tum-buckles extending transverse1y 0f theform and detachabiy secured t0 the ribs at the'ir ends by means'of theb01ts 1,1. The wings are held against swinging m.ovemant whei1 in ope}nposition by xmians of the hooks 12. The two wings 8 und 9 um preferablyused instea. 0f a singla langer wing as th6 two wings are morga easilyde'mched andsecured in open positiem und occupy less spape dlgring thesxyinging movemen}, than does a Single wing. Additional mrticalturnbuckles 19 may also sometimes be' employed to hold the sectioncoliapse&

In orer t0 pemni 0f the ready movement cf t'ne coilapsed sectionsthrough the other sections, the Sets 013 rollers 13, 14 and 15 arepzovided, which milers are secured t0 the ribs by mea.ns f tne ciipssh0wn in Fig. 2 From Fig. 1 it will be seen that when the section iscollapse ii: fits freelv inside of an- 0tney section, and that thsroliers 13, 14 und 15 will supp0rt die exteri0r surface 0f t;h

co'iapsred sectioh und per1nit its reac.y move: men's tzmugh 1e expandedsectmns. As in icated in Fig. 2 i;lxe sections are secured d :ah abiytogether m; mezmsof the bolts 1B, x:h nass twaugzh the fianges 0'f thechannels 1 and 3 and through the flanges of the channels 17 and 18constituting the und ri0s up0n other sections 0f the f0rm which areprecisely the Same in construetion and opera' tion as the one heretoforeillustrated and described.

The invention is of course not limited in its application t0 forms whichare of the true circular eross section shown, and it will be understoodthat the term eircular as employed is used in its generic sense t0designate complete m0ld sections as opposed t0 the incomplete forms 0finverted U cross section open at the bottom. It will also be understoodthat th-e invention is not limited to the use of the tw0 wings 7 and 8,although this is the preferred construction.

Having thus described my invention and illustrated its use, what I claimas new and desire tx secure by Letters Patent is the following l. Incombinat-ion in a collapsible m01d, supporting ribs covered With laggingand comprising main rib portions, and relatively short portions hingedto the ends thereof with knuckle joints so as t0 swing inwardly,

and lying at the t0p of the n101d, the said ribs being sufficientlyyielding t0 spring inwardly when the hinged portions are swnng inwaidly,but sufiiciently stifi' t0 rnaintain the mold' in expanded position leaving the interior of the mold unobstructed when the hinged portions arein their outer operative position.

2. In combination in a collapsible m01d, supporting ribs covered Withlagging and. comprising main rib portions, and relativel short portionshinged t0 both ends 0f eac main rib With knuckle joints so as to swinginwardly but nofioutwardly past operative position, the Said ribs beingsufliciently yielding to spring inwardly When the hinged portions areswung inwardiy, but sufliciently stifl t0 maintain the mold in expandeposition leaving the interior of the mold unebstructed when the hingedportions are in their outer operative position.

3. In combination in a collapsible mold, supporting ribs covered withiagging and comprising main rib portions, .and relatively short portionshinged t0 the ends thereef and constructed t0 swing inwardly fro moperative osition but n0t ouwardly past such position, the said ribsbeing suificiently yielding t0 spring inwardly when the hinged portionsare swun invvardly, but sufficiently stifi? to maintain t e mo ld inexpanded position leaving the interior 0f the rn0ld unobstructed whenthe hinged portions are in their outer operative position.

In fiestimony whereof I have hereunto signed rny name in the presence 0fthe tw0 subscribed witnesss.

CHARLES D. MCARTHUR.

Witnesses:

J. C. BRADLEY, DOERING BELLINGER.

